Latching fittings are used, for instance, as adjusting elements for motor vehicle seats. The latching fittings allow a movement of the backrest into a desired position. Generally there is a region in which the backrest can be moved for adjusting to a desired seat position, and one or more regions that only allow a fixed backrest position. In these positions, a loading area can be increased, for instance. Latching fittings are also known as hinge fittings, fittings or latching adjusters.
DE 101 02 860 A1 discloses a latching fitting for a motor vehicle seat with at least one bolt movable in radial direction.
From DE 20 2008 001 597 U1 a latching fitting is known which comprises a plurality of pivotable or movable blocking sections. The blocking sections are arranged on a driver plate and can be guided from the outside and locked to a ring gear.
DE 20 2007 012 931 U1 discloses a latching fitting with an internally toothed fitting part which is rotatable relative to a first fitting part, and with an eccentric which is drivable and mounted rotatable around an axis and which is able to move toothed segments or bolts in radial direction and to lock a so-called play-compensation element.
DE 10 2006 032 681 A1 displays a hinge fitting with a driving member having a non-circular drive portion, with an internally toothed first hinge part and a second hinge part and with blocking arms which co-operate with the internal toothing.
WO 00/06414 discloses a latching fitting with a housing and a cover plate which encloses the housing. The cover plate has an outer ring with a plurality of teeth. Three toothed arms are arranged in the circumferential direction of a support plate and are actuated by a drive member, which is biased in the locking direction by a spring.
WO 2005/044617 A1 discloses a hinge fitting for a motor vehicle that is provided with at least two blocking arms.
EP 1 260 405 A1 discloses a latching adjuster which has rotatable toothed levers that can mesh with an internal toothing which is provided in an intermittent manner.
From DE 32 11 158 A1 a hinge fitting for an adjustable backrest is known.
DE 10 2006 056 004 A1 describes a hinge fitting that has two mirror-inverted pairs of toothed levers.
The latching adjuster disclosed in DE 11 2007 001 388 T5 has a plurality of toothed levers, an activating plate and an intermittently provided internal toothing.
EP 1 818 210 B1 discloses an inclination adjustment mechanism for a vehicle seat that has sliding toothed levers, an actuation plate, and an intermittent internal toothing.
In WO 2008/130075 A1 a latching fitting is described that comprises a cover plate which has an inner toothing, and a support member which is rotatable relative to the cover plate. In addition, the latching adjuster comprises a plurality of toothed levers for providing a form-fitting connection between the cover plate and the support member. The toothed levers are pivotally/rotatably arranged on the supporting member. One single tooth lever has a latching projection. The cover plate has an inner circumferential portion below the inner toothing which projects towards the center of the cover plate and engages with the latching projection.
The latching adjuster disclosed in DE 11 2009 000 118 T5 comprises a cover plate which has an internal toothing, a support member which is rotatable relative to the cover plate, and a fixed control ring. In addition, the latching adjuster comprises four toothed levers for providing a form-fitting connection between the cover plate and the support member. A toothed lever has a latching projection which can engage in the control ring.
DE 10 2007 027 341 A1 discloses a latching adjuster that comprises a cover plate, which has an internal toothing, a supporting member which is rotatable relative to the cover plate, and a fixed control ring. In addition, the latching adjuster comprises four toothed levers which are arranged pivotally at the support member. Each toothed lever has a latching projection, which can engage in the control ring.
The known latching fittings are designed in a way that they have essentially the same cogging torque for both directions of rotation. The cogging torque is the torque that the latching fitting can reliably absorb before a malfunction may occur, such as slipping or even the rupture of the latching fitting. In the known latching fittings, complex control curves are employed, too, in order to prevent slipping of the latching fitting, and to ensure a reliable blocking function.
It is the object of the invention to provide a latching fitting that has a significantly larger cogging torque in one direction of rotation than in the other direction of rotation.
This object is solved by a latching fitting according to claim 1. Preferred embodiments of the latching fitting are specified in the claims.